We propose the establishment of a Maternal-Fetal Medicine Unit (MFMU) at the University of Chicago's Department of Obstetrics and Gynecology. Principal and Co-principal investigators have extensive experience in both clinical and basic research, while the team of investigators includes seven maternal-fetal medicine specialists, a neonatologist, two internists who specialize in medical disorders of pregnancy, a statistician experienced in the conduct of clinical trials, and a proven nurse-educator coordinator with a M.P.H. degree. Three other research nurses are also available for trials. The applicant institution, houses a State of Illinois designated Perinatal Center, and experiences ~3200 births yearly of which ~50% are high risk including a 22% prematurity rate. Other major problems include low birthweight, drug use and hypertension. The neonatal intensive care unit, next to the delivery suite is licensed for 37 beds and is served by five neonatologists. Most gravidas are managed by full-time faculty, and there are four "high risk" clinics, each of which contain a computerized record system which captures comprehensive information on all patients and produces a wide variety of reports used throughout the hospital. Available services for prenatal and intrapartum diagnosis include Doppler velocimetry ultrasound, electronic fetal monitoring, chorionic villus sampling, amino- and cordo-centesis. Our pharmacy has a specialized trials section and laboratory support includes cytology, genetic diagnosis, and perinatal pathology. The proposed MFMU meets all other requirements listed in the RFA solicitation including readiness to participate in a capitation system. In summary, this is an application for an MFMU, from an institution with a strong academic presence and history of caring for pregnant women, which has the capacity and desire to participate in the Cooperative National Network and with all the in-house expertise necessary for clinical trials.